How can I set QTableWidget header item background color to initial value?

[iskenderoguz]

I change background color of QTableWidget horizontal header item to red with this code:

ui->tbl->horizontalHeaderItem(0)->setBackgroundColor(Qt::red);

After that I want to set color to initial value. How can I do that ?

I tried to get initial value with ui->tbl->horizontalHeaderItem(0)->setBackgroundColor() but it returns QColor(invalid).